Antenna Length Calculator
Calculate quarter-wave and half-wave antenna lengths from a given frequency.
Supports output in meters, centimeters, feet, and inches.
Antenna Length
Antenna length is based on the wavelength of the target frequency.
Wavelength (λ) = Speed of Light / Frequency
Half-wave antenna = λ / 2
Quarter-wave antenna = λ / 4
Where the speed of light ≈ 299,792,458 m/s.
Unit conversions:
- Meters — base unit
- Centimeters — meters × 100
- Feet — meters × 3.28084
- Inches — meters × 39.3701
Common frequencies:
- FM radio (88–108 MHz): ~1.4–1.7 m half-wave
- Wi-Fi 2.4 GHz: ~6.25 cm half-wave
- Wi-Fi 5 GHz: ~3 cm half-wave
- LoRa 915 MHz: ~16.4 cm half-wave
A velocity factor of 0.95 is applied to approximate real-world conductor shortening.